The present invention relates to the production of compound filters, and more particularly to horizontal assembly of multiple filter components of compound cigarette filters.
U.S. Pat. Nos. 3,517,480 and 3,603,058 illustrate and describe machines for the production of composite cigarette filters by directly flowing granular filter material from a storage hopper into a vertically oriented filter tube made of paper. Similarly, US Patent Application Publication 2002/0119874A1 describes another vertical filling machine for producing compound cigarette filters that includes a series of rotating plates with cavities therein into which the granular filter material is deposited. The cavities ultimately are aligned with a vertically oriented open ended filter tube of paper to facilitate deposit of the granular material into the tube. These machines have the disadvantage of often destroying the integrity of the paper filter tubes into which filter materials are deposited. They also deposit imprecise amounts of granular material and produce undesired amounts of fine dust and the like.
Co-pending and commonly assigned application Ser. No. 11/268,291, filed Nov. 4, 2005, also relates to machinery and processes for producing compound cigarette filters utilizing vertical filling techniques that avoid the disadvantages of the above-described disclosures. However, the invention of this application also relies on vertical procedures for compound filter assembly.